Seven-times champion Williams, was handed the final women's singles wildcard by the All England Club on Sunday evening (Monday AEST) in a wholly unexpected and sensational development after playing only two doubles matches in her recent comeback.
The woman considered perhaps the greatest player of all-time had already been assured of a shock return to the championships for the first time in four years by accepting a doubles wildcard to play alongside elder sister, 46-year-old Venus Williams.
But the singles news came quite out of the blue, after she effectively laughed off the idea earlier in the month by suggesting: "You think I'm ready for singles? I need to get to work."
But Wimbledon dropped the bombshell on its Instagram account, declaring: "This is not a drill."
It means the 23-time grand slam singles champion will return to court, either a week next Monday or Tuesday, at the All England Club to play a match which will be watched with fascination around the world.
Williams' last singles match at Wimbledon came as a wildcard in 2022 when she lost to Frenchwoman Harmony Tan in round one, and she hasn't won a match there since 2019, when she lost in the final to Simona Halep..
After the 2022 US Open, when she lost to Australian Ajla Tomljanovic in what everyone assumed would be the final match of her extraordinary career, she declared she would "evolve away from tennis", while never actually ever declaring she was officially retired.
She returned amid much fanfare to make a winning return to the doubles court at the Queen's Club Championship alongside Victoria Mboko a fortnight ago but an injury to the young Canadian halted their progress.
She then lost in her next doubles match last week alongside Czech Karolina Muchova in Berlin, succumbing 6-4 6-4 to Erin Routliffe and Giuliana Olmos.
Williams had largely impressed in her doubles return, suggesting it was "about time" she returned as she mentioned recent comebacks by two other US female greats, ski racer Lindsey Vonn and track ace Allyson Felix.
Yet singles fare is a completely different matter and, despite her greatness, it would still be utterly astonishing if she could prevail in her first match back in anger.
"You can do anything at any age," Williams protests. "It doesn't matter as long as you're healthy and you take care of yourself and you're happy and you're doing your best - it's really all that matters."
It's now 28 years since Williams first made her appearance at on the grass courts of SW19, when she reached the third round, and four years later, she became champion, beating Venus in the final, going on to spend a combined total of 319 weeks as world No.1 while grabbing a career-haul of 73 singles titles.
She will learn her first-round opponent when the draw takes place at Wimbledon on Friday.
